Perceptual lateralization on the Rod-and-Frame Test in young and older adults.

INTRODUCTION: There is an overall left visual field/right hemisphere advantage in young adults for masked, tachistoscopically presented images on the Rod-and-Frame Test (RFT). This study explored potential age-related lateralization differences in processing of visual context on the RFT. METHODS: The 35 young and 33 older adults aligned a rod surrounded either by no frame, a vertical, or leftward/rightward tilted frame to their perceived vertical. Algebraic errors of rod alignment were used to derive the rod-and-frame effect (RFE) and asymmetry index. RESULTS: Young adults had frequent indirect effects, mostly to the right-tilted frame, while older adults hardly produced any. Compared with nontilted frames, young adults displayed larger alignment errors with left-tilted frames; however, older adults exhibited this same effect for both frame tilt conditions. Young adults had smaller RFE values than older adults for the right-tilted frame, with no age-related difference in RFE for the left-tilted frame or asymmetry index. The negative asymmetry index was statistically different from the true vertical only in young adults. CONCLUSION: There is an age-related reduction in the right hemisphere processing of left-sided visual contexts on the RFT. Such findings can assist clinicians to improve interpretation of RFT findings in clinical patients.

Do students effectively learn physiology through distance online instruction? Medical students' perceptions and academic performance.

This an account of student feedback on the distance online tools adopted at the onset of the COVID-19 pandemic for teaching cardiovascular (CVS) physiology to Year 2 medical students within a problem-based learning (PBL) medical curriculum. Students' achievement upon assessment of CVS physiology theory content was also evaluated. Most students were ready for online learning in terms of appropriate equipment and internet connectivity. Most students expressed a preference for face-to-face learning of CVS physiology; however, they relied on recorded videos mainly for learning, instead of real-time attendance of physiology learning activities. Most students also reported a negative experience of distance online learning of CVS physiology during the lockdown, and only a few students expressed connection with their instructor through the physiology learning activities. Students undertaking online learning and examination during the pandemic achieved comparably to the prior year's cohort of PBL students learning in person and undertaking paper-based assessment. This indicates that our medical students preferred asynchronous learning during the pandemic confinement and that they sufficiently achieved their learning outcomes in CVS physiology, displaying resilience in their adaptation to the online learning and examination format.

Young and Older Adults Differ in Integration of Sensory Cues for Vertical Perception.

INTRODUCTION: The subjective visual vertical (SVV) measures the perception of a person's spatial orientation relative to gravity. Weighted central integration of vestibular, visual, and proprioceptive inputs is essential for SVV perception. Without any visual references and minimal proprioceptive contribution, the static SVV reflects balance of the otolith organs. Normal aging is associated with bilateral and progressive decline in otolith organ function, but age-dependent effects on SVV are inconclusive. Studies on sensory reweighting for visual vertical and multisensory integration strategies reveal age-dependent differences, but most studies have included elderly participants in comparison to younger adults. The aim of this study was to compare young adults with older adults, an age group younger than the elderly. METHODS: Thirty-three young and 28 older adults (50-65 years old) adjusted a tilted line accurately to their perceived vertical. The rod's final position from true vertical was recorded as tilt error in degrees. For otolithic balance, visual vertical was recorded in the dark without any visual references. The rod and frame task (RFT) with tilted disorienting visual frames was used for creating visuovestibular conflict. We adopted Nyborg's analysis method to derive the rod and frame effect (RFE) and trial-to-trial variability measures. Rod alignment times were also analyzed. RESULTS: There was no age difference in signed tilts of SVV without visual reference. There was an age effect on RFE and on overall trial-to-trial variability of rod tilt, with older adults displaying larger frame effects and greater variability in rod tilts. Alignment times were longer in the tilted-frame conditions for both groups and in the older adults compared to their younger counterparts. The association between tilt accuracy and tilt precision was significant for older adults only during visuovestibular conflict, revealing an increase in RFE with an increase in tilt variability. Correlation of σ SVV, which represents vestibular input precision, with RFE yielded exactly the same contribution of σ SVV to the variance in RFE for both age groups. CONCLUSIONS: Older adults have balanced otolithic input in an upright position. Increased reliance on visual cues may begin at ages younger than what is considered elderly. Increased alignment times for older adults may create a broader time window for integration of relevant and irrelevant sensory information, thus enhancing their multisensory integration. In parallel with the elderly, older adults may differ from young adults in their integration of sensory cues for visual vertical perception.

Circulating endothelium-enriched microRNA-126 as a potential biomarker for coronary artery disease in type 2 diabetes mellitus patients.

Circulating microRNAs (miRNAs) have been shown as promising biomarkers for various diseases. We investigated the predictive potential of circulating endothelium-enriched miR-126 in type 2 diabetes patients (T2D) without chronic complications and T2D patients with coronary artery diseases (CAD). The expression levels of circulating miR-126, determined by quantitative real time PCR, were decrease in peripheral blood of T2D patients and T2D with CAD compared with healthy controls. MiR-126 strongly associated with T2D and CAD, negatively correlated with LDL in CAD patients and differentiated between T2D patients, T2D patients with CAD and healthy subjects. Circulating miR-126 may serve as a biomarker for predicting patients with T2D and diabetic CAD.

Postural visual dependence in asymptomatic type 2 diabetic patients without peripheral neuropathy during a postural challenging task.

UNLABELLED: Increasing evidence indicates that diabetes may negatively affect vestibular function, and postural control more so under postural challenging conditions. Healthy and diabetic subjects were compared on visual control of posture during a postural challenging task. METHODS: Forty-eight asymptomatic patients with type 2 diabetes free of peripheral neuropathy and 29 age-matched normal subjects were compared on postural stability on a high-density foam block with computerized posturography. Sway parameters were measured and Romberg ratios calculated and compared between the two groups. RESULTS: For subjects who succeeded in maintaining balance, all sway parameters were larger in the diabetics with vision available. With eye closure, only the sway area was almost significantly larger and of greater variability in diabetics, but with a smaller and less variable Romberg ratio. Among the two groups and visual conditions, the tightest anterioposterior-mediolateral (AP-ML) coupling was found in diabetics during eye closure. Differences in anthropometric factors did not influence postural sway. CONCLUSIONS: Despite the smaller Romberg ratios in diabetics than controls, findings still suggest greater but masked postural visual dependence in diabetics faced with postural challenging situations due to subclinical vestibular deficits. They also indicate that diabetics may be vulnerable before any clinical signs of peripheral neuropathy arise to falls on unstable surfaces especially in poorly lit areas, and may require to employ other complex postural tactics such as stiffening to maintain their balance.

Preliminary blood pressure screening in a representative sample of extremely obese Kuwaiti adolescents.

A relationship between blood pressure (BP) and obesity has been found in young adults, but no data are available for adolescents in Kuwait. 257 adolescent (11-19 years) participants were categorized into two groups according to their BMI; 48 nonobese (21 males: 43.7% and 27 females: 56.3%) with mean age of 15.61 ± 2.40 years and 209 obese (128 males: 61.25% and 81 females: 38.75%) with mean age of 15.02 ± 2.82 years. The mean BMI was 21.7 ± 2.23 kg/m(2) for the nonobese group and 34.47 ± 4.70 kg/m(3) for the obese group. Most BP measures based on a single screening were significantly higher in the obese group. The prevalence of elevated BP was significantly higher in the obese subjects (nonobese: 13%; obese: 63%; P < 0.0001). In the obese group, there was a significant positive correlation between total sample BMI and all BP measures except the pulse pressure. There was a similar rate of elevated blood pressure between males and females (64% versus 60%; P = 0.66). For both isolated systolic elevated BP and isolated diastolic elevated BP, the prevalences were comparable between the males (systolic: 42%; diastolic: 5%) and females (systolic: 34%; diastolic: 14%). Only systolic BP was positively correlated with BMI in obese adolescent males (Spearman r = 0.18; P < 0.05), with a significant correlation between BMI with diastolic (Spearman r = 0.22; P < 0.05) and mean BP (Spearman r = 0.21; P < 0.05) in females.

A preliminary study on the Trail-making Test in Arabic-English bilingual young adults.

The Trail-Making Test (TMT) is used in different neuropsychological test batteries. It consists of two parts: TMT-Part A, which tests visual scanning and psychomotor speed, and TMT-Part B, which assesses more complex cognitive processes. TMT normative data have been established in many non-Arab countries either using the original English version or a version developed with the native language. The aim of this study was to compare TMT performance between the English TMT and a constructed Arabic TMT in young Arabic-English bilingual college students from three Arabian Gulf states. Scores from 83 participants who took the English TMT and 52 who took the Arabic TMT were included. Arabic TMT (both parts) scores were significantly poorer compared with English TMT scores. Arabic TMT scores were also poorer than were other norms for this age group and education level, but they were better than those reported from another study using the Arabic TMT. Moreover, there were nonsignificant differences in performance between participants from these three countries; however, these findings are inconclusive as sample sizes were small. These findings suggest that Arabic TMT norms cannot be unified for all Arabic countries, and separate Arabic TMT norms including all age groups and education levels must be established for each Arabic country.